Disk construction for radial flow machines



April 26, 1938. u. MEININGHAUS 2,115,031

DISK CONSTRUCTION FOR RADIAL FLOW MACHINES ori inai Filed March 22, 1932 J6 if 60 I s 60 I a7 r 7 .5' as A k x E Q Wyn/r04? Mammal/40$ Patented Apr. 26, 1938 UNITED STATES PATENT OFFICE DISK CONSTRUCT;::::)R RADIAL FLOW Ulrich Meininghaus, Muelhcim-Buhr, Germany .Origlnal application March 22, 1932, Serial No. 600,500. Divided and this application June 8, 1935, Serial No. 25,676. In Germany February 13 Claims.

My invention relates to the construction of disks for use in machines wherein they are exposed to the action of a heated pressure medium and are subjected to axial thrust and torque, as in a radial flow turbine where they support the turbine blades. Disks of this kind have been claimed in my copending application Ser. No. 600,500, filed March 22, 1932, and this application is a division of such earlier'application.

As already described in my copending application Ser. No. 600,500, disks carrying blades of radial flow machines are conveniently supported by elastic annular members in order to allow the disks to expand or contract freely with any change in the state of heat of the working medium. If the disks are built up of a great number of rings or of rings of, large diameter a considerable deformation of the elastic annular members supporting them arises from the expansion or contraction due to temperature changes or-in the case of rotating disks-from the expansion due to centrifugal force. In order to keep the stresses hereby arising in the elastic annular elements within permissible limits, the supporting elastic annular elements must be constructed 7 with comparatively thin walls. -The thin walled elastic annular elements are not able to withstand high additional stresses such as arise from the torques and thrusts which occur with blade carriers in radial flow machines.

It is the object of my present invention to relieve the thin walled elastic annular elements which support the bladed disks from such additional stresses, and I propose to provide means for transferring the torque or thrust directly from the disks to the machine part supporting the disks and operating to relieve the thinwalled elastic annular elements of the transfer of the torque or thrust, said means engaging with radially extended surfaces of the disks and allowing free movement of the disks in a radial direction.

On the accompanying drawing, which shows by way of example a satisfactory embodiment of the invention, Fig. 1 shows a section through a radial flow turbine embodying theinvention; and Fig. 2 is a section along the line 11-11 of Fig. 1.

In the turbine shown in Fig. 1, the blades or rows of blades 38 and 39 are supported by disks 40, 4 I, 42, 43, and 44, such disks being constructed according to my copending application Ser. No. 600,500. The structural elements of the disk 4|, for instance, are the root rings 45 which support one end of the blades 38. Said elements are linked to each other by elastic joints 46. The other ends of the blades 38 are supported by the head rings 41. Steam enters through the inlet pipe 40, flows in an outward direction through the rows of blades where it gives ofi part of its work, streams back through the conduit 40 towards the shaft, and impinges now the row of blades 39again in radial direction giving on the remainder of its work and leaving the turbine at 50. As it does work the steam expands and gradually drops in pressure. A pressure difference between the two sides of the above mentioned disks consequently arises creating an axial thrust. At the same time a torque is created in the blade rows by the action. of .the steam,- the sum of the torques of the blade rows being transmitted to the disks.

The elastic joints ofthe disks connecting the root rings are arranged at one end of said root rings; this arrangement has the advantage that the steam flows through the blades in an outward direction only, the area of fiow increasing with the diameters of the rings in accordance with the expansion of the steam. To relieve the bending stresses causedby the centrifugal force resulting from the unbalanced arrangement. and also the radial stresses caused by differential expansion the disks 43 and 44 have been separated and linked by the elastic annular element 5l. This thin walled elastic annular element is re-' .lieved of the thrust by the shoulders 52 and 53.

The disks 4|, 43, and 4 4 rotate and are fastened to the shaft 54 which is supported by the bearing 55; the disks 40 and 42 are stationary and supmembers tothe shaft 54. The members 60, as shown, are of. U-shape, being connected at one edge integrally with the disks and at the other to the shaft, the intermediate portion lying in- 5 wardly of the respected disks. To obtain sufficient flexibility the walls of the elastic annular members are so thin that for instance the annular members 60 of the rotatingdisks are'not strong enough to transfer the great circumferential force,

due to the torque when their diameter is small, as the circumferential force increases with decrease of' the diameter. To relieve the thin walled elastic annular member 60 from the torque a key 6| is provided'at the shaft which fits with its surfaces'extending lnradial directionin a riotous shoulder 62 or the disk 4| (see Fig.2).

In this way the torque is transferred directly from the'disk 4| to the shaft I4 thereby relieving V thethin walled elastioannular member 60 from the torque without interfering with the free expans'ion' or contraction of the disk ll in radial direction. The torque of the disk is transferred in a' similar wayby the surfaces of the projection 63' of the disk extending in radial direction and fitting in a slot 84 on the shaft.

Thethin walled elastic annular elements are also relieved of the thrust for the same reason. The disks ll and 43 rest with the surfaces 65 and 86 which extend also-in radial direction against corresponding-"shoulders on the shaft. Also these surfaces do not interfere with the free radial expansion or contraction of the disks. The thin walledelastic annular elements 60 which are integral with'the rotating disks are fastened to the shaft 54 by caulking the free end into anotch by means of caulking'wire as shown at '1; this wayof fasteninginsures a Joint whichmay always easily be separated and again renewed in I spite of thefact that the joint is'subjected tothe action'of the hot steam; Besides, the joint takes verylittle spacein radial and axial direction.

This latter feature is of; great importance if a rather large number of "dis'ksi's' to be employed, "as the joints increase in diameter'to allow for assembling .the integral disksendwisef on the shaft,and an additionalleng'th ofjoint will occur ,with each diskgthus resulting in, an excessive additional length On the other hand, a large number'of disks is desir'ablebecauseit produces increased emciency and diminishes of the'rather highaxial thrusts which occur in radial flow machines, as described in my copending application VSE'I; N0. 671,442. 1

The thin walled, elasticannular element 60 has tendency to heat up and-{cool ofl'faster than the heavy machine part-'towhich the element is connected by'caulkin'g (shaftil); 'Theidlflferential expansion or contraction caused in this way will bring the surfaces '65 and 6* out of con- .1 tact, with the shaft or press them against the shaft, thus imposing an and: thrust on the thin walled, elastic member 50. 'In' order to render harmless the temporaryover'expansions' or conv tractions of the annular members 60 the point of connection of said annular member 60- to the shaft 54 'isarranged in, substantially the same radial plane as the radially extending surfaces I so 65 or 66 for transferring the thrust; The annular member 60 can; now expand or contract without changing the axial position of thesurfaces' 65 I claim: a

l. The combination with a rotary disk having axially extending, radially impin e turbine blades thereon, said disk being subjected in use to'the different pressures of the driving medium at the opposite sides'thereof' and to a resultant I 1 fthrustin one direction, of a rotating machine part supporting said disk, radiallyextendlng surfaces onsaid disk and said machine part engageable withreach other in the axial direction, and

I -anelastic annular member tightlyfconnected along oneedge to said disk andalongthe other arranged in substantially the same, radial plane a with said 75 edgeto said machine part tojpreventleakage of v the driving mediumfrom one sidejof said disk to x the other, the line of connection of said elastic annular member with said ,machine' part being radially extending surfaces to enable saidfradially' extending surfaces to' cooperate shaft adjacent to -the shoulder,

' said .disk, said shaft having a elastic annular memberd for above the reduced portion with each other, apart from said elastic member, s to substantially relieve said elastic annular member of the transfer of thethrust from said pressure loaded disk to said machine part. 1 2. The combination asset forth in claimrl, 5 wherein both lines of connection of the elastic annular member with the disk and with the t machine part are arranged insubstantially the I same radial plane with said radially extending I 5 surfaces.

I 1 r 1 l0 3. The combination with a rotary disk having a axially extending,radially impinged blades there a on, said disk being subjected in use to the different 1 1 pressures of the driving medium at the opposite sides thereof and to a resultant thrust in one di- 16 rection, of a rotating shaftsupportingsaid disk and provided with a shoulder,- the inner diameter of said disk being smaller than the outer diameter of said shoulder, the surface of therdisk' at the low pressure'side of the disk being-arranged tdzo bear against the shoulder in the loaded condition of the disk to transfer the thrustonthe disk to the shaft'by way of suchshoulder, the blades-on. I said disk overlying the reduced and-an elastic- 5 annular member untensioned in the stationary condition of the disk and attached to the disk and to the shaft, said annular member providing a in seal between the disk and shaft. 1 1' 4. The combination as setforth in claim"1.'

whlerein the annular member is integral with the 5. The combination as set forth. in claim 1, wherein the annular member is'of U-cross-section.- .v

6. The combination as set-forth in claim 1', wherein the radially extending surfaces are located at approximately the diameter ofthe an-' 'nular member. I

'7. The combination as set forth in claim 3, 0

wherein the annular member isjof U-shape and is directly connected to the disk and to the shoulder in approximately the same-radial plane. 1 8. The combination withra 'rotary'disk having axially extending, radially; impinged turbine. H blades thereon, said disk being subjected in use'toj the different pressures of the driving mediumv at the opposite sides thereof and to a resultant thrust in one direction, of a rotary shaft supporting said disk and having and an elastic annular member connected tosaid 7 disk and directly connected to saidshoulder, said disk and shoulder having opposing surfaces extending in an approximately radialdirectionand directly engageable with each otherin the axial Y direction, said surfacesbeing disposed at approximately thev same diameter'as said elastic annular member and cooperating with each other, apart from said elastic annular membe -to substantially relieve said member of thetransfer'of the 00 thrust from the disk to the'shaft. 7

Y 9. The combination with a rotary disk having axially extending, radially impinged turbine blades thereon, said 'disk' being subjected in use to the difl'erent pressures of the driving medium 66' I from the reduced portion 'of theshaft,the con-..761 I 1 portion of a shoulder thereon, I

nection between said member and the shaft being accessible through such space for disconnecting the disk, with the annular member attached thereto, from the shaft, said disk engaging said shoulder in the axial direction to transmit the axial thrust to the shaft and thereby relieve the annular member of the transferof said thrust.

10. The combination as set forth in claim 9, wherein the annular member is of U-cross-section and is connected by caulking to the shoulder, said member being spaced a suflicient distance from the reduced portion of the shaft for the insertion of a caulking tool therebetween.

11. The combinationset forth in claim 9, including means on the disk and shoulder intergaging in a circumferential direction for transferring the torque to the shaft.

12. The combination with a rotary disk having axially extending, radially impinged turbine blades thereon, said disk being subjected in use to the different pressures of the driving medium at the opposite sides thereof and to a resultant thrust in one direction, of a shaft for supporting said disk, an elastic annular member along one edge to said web, the other edge of said member being connected to the shaft, means on said shaft presenting an approximately radially extending surface against which said web bears to transfer the thrust on the disk to the shaft, and means on said shaft and web presenting opposed surfaces engaging in the circumferential direction for transferring the torque from the disk to the shaft.

13. The combination as set forth in claim 12 wherein the last-mentioned means is positioned upon the side of the web opposite that of the blades. ULRICH MEININGHAUS. 

